Search Results (568)

This review explores the biofilm architecture and drug resistance of Enterococcus faecalis in clinical and environmental settings. The biofilm in E. faecalis is a heterogeneous, three-dimensional, mushroom-like or multilayered structure, characteristically forming diplococci or short chains interspersed with water channels for nutrient exchange and waste removal. Exopolysaccharides, proteins, lipids, and extracellular DNA create a protective matrix. Persister cells within the biofilm contribute to antibiotic resistance and survival. The heterogeneous architecture of the E. faecalis biofilm contains both dense clusters and loosely packed regions that vary in thickness, ranging from 10 to 100 µm, depending on the environmental conditions. The pathogenicity of the E. faecalis biofilm is mediated through complex interactions between genes and virulence factors such as DNA release, cytolysin, pili, secreted antigen A, and microbial surface components that recognize adhesive matrix molecules, often involving a key protein called enterococcal surface protein (Esp). Clinically, it is implicated in a range of nosocomial infections, including urinary tract infections, endocarditis, and surgical wound infections. The biofilm serves as a nidus for bacterial dissemination and as a reservoir for antimicrobial resistance. The effectiveness of first-line antibiotics (ampicillin, vancomycin, and aminoglycosides) is diminished due to reduced penetration, altered metabolism, increased tolerance, and intrinsic and acquired resistance. Alternative strategies for biofilm disruption, such as combination therapy (ampicillin with aminoglycosides), as well as newer approaches, including antimicrobial peptides, quorum-sensing inhibitors, and biofilm-disrupting agents (DNase or dispersin B), are also being explored to improve treatment outcomes. Environmentally, E. faecalis biofilms contribute to contamination in water systems, food production facilities, and healthcare environments. They persist in harsh conditions, facilitating the spread of multidrug-resistant strains and increasing the risk of transmission to humans and animals. Therefore, understanding the biofilm architecture and drug resistance is essential for developing effective strategies to mitigate their clinical and environmental impact. Full article

The incorporation of nucleoside analogs into DNA by polymerases, followed by their removal through base excision repair (BER), represents a promising strategy for cancer chemotherapy. In this study, we investigated the incorporation and cytotoxic effects of several nucleoside analogs—some of which are epigenetic reprogramming intermediates—in the U87 glioblastoma cell line. We found that two analogs, 5-hydroxymethyl-2′-deoxyuridine (5HmdU) and trifluorothymidine (TFT), are both cytotoxic and are efficiently incorporated into genomic DNA. In contrast, the 5-carboxy analogs—5-carboxy-2′-deoxyuridine (5CadU) and 5-carboxycytidine (5CadC)—showed no cytotoxicity and were not incorporated into DNA. Interestingly, 5-hydroxymethyl-2′-deoxycytidine (5HmdC) was cytotoxic but was not directly incorporated into DNA. Instead, it was deaminated into 5HmdU, which was then incorporated and likely responsible for the observed toxicity. 5HmdU is actively removed from DNA through the BER pathways. In contrast, TFT remains stably incorporated and is neither excised by BER nor does it hydrolyze into 5CadU—a known substrate for the DNA glycosylase SMUG1. We also found that N⁶-benzyladenosine (BzAdo), an inhibitor of the enzyme 2′-deoxynucleoside 5′-phosphate N-hydrolase (DNPH1), enhances the cytotoxicity of 5HmdU. However, the thymidine phosphorylase inhibitor tipiracil hydrochloride (TPI) does not increase the cytotoxic effect of TFT in U87 cells. Together, these findings highlight 5HmdU and TFT as promising chemotherapeutic agents for glioblastoma, each with distinct mechanisms of action and cellular processing. Full article

The transition to sustainable energy sources has intensified interest in lignocellulosic biomass (LCB) as a feedstock for second-generation biofuels. However, the inherent structural recalcitrance of LCB requires the utilization of an effective pretreatment to enhance enzymatic hydrolysis and subsequent fermentation yields. This manuscript presents a novel, single-step, and optimized nitrogen explosive decompression system (NED 3.0) designed to address the critical limitations of earlier NED versions by enabling the in situ removal of inhibitory compounds from biomass slurry and fermentation inefficiency at elevated temperatures, thereby reducing or eliminating the need for post-treatment detoxification. Aspen wood (Populus tremula) was pretreated by NED 3.0 at 200 °C, followed by enzymatic hydrolysis and fermentation. The analytical results confirmed substantial reductions in common fermentation inhibitors, such as acetic acid (up to 2.18 g/100 g dry biomass) and furfural (0.18 g/100 g dry biomass), during early filtrate recovery. Hydrolysate analysis revealed a glucose yield of 26.41 g/100 g dry biomass, corresponding to a hydrolysis efficiency of 41.3%. Fermentation yielded up to 8.05 g ethanol/100 g dry biomass and achieved a fermentation efficiency of 59.8%. Inhibitor concentrations in both hydrolysate and fermentation broth remained within tolerable limits, allowing for effective glucose release and sustained fermentation performance. Compared with earlier NED configurations, the optimized system improved sugar recovery and ethanol production. These findings confirm the operational advantages of NED 3.0, including reduced inhibitory stress, simplified process integration, and chemical-free operation, underscoring its potential for scalability in line with the EU Green Deal for bioethanol production from woody biomass. Full article

The extracellular matrix (ECM) is a collagen-based scaffold that provides structural support and regulates nutrient transport and cell signaling. ECM homeostasis depends on a dynamic balance between synthesis and degradation, the latter being primarily mediated by matrix metalloproteinases (MMPs). These enzymes are secreted as pro-forms and require activation to degrade ECM components. Their activity is modulated by tissue inhibitors of metalloproteinases (TIMPs). Aging disrupts this balance, leading to the accumulation of oxidized, cross-linked, and denatured matrix proteins, thereby impairing ECM function. Bruch’s membrane, a penta-laminated ECM structure in the eye, plays a critical role in supporting photoreceptor and retinal pigment epithelium (RPE) health. Its age-related thickening and decreased permeability are associated with impaired nutrient delivery and waste removal, contributing to the pathogenesis of age-related macular degeneration (AMD). In AMD, MMP dysfunction is characterized by the reduced activation and sequestration of MMPs, which further limits matrix turnover. This narrative review explores the structural and functional changes in Bruch’s membrane with aging, the role of MMPs in ECM degradation, and the relevance of these processes to AMD pathophysiology, highlighting emerging regulatory mechanisms and potential therapeutic targets. Full article

Alzheimer’s disease (AD) is a progressive, complex, multifactorial, neurodegenerative disease and accounts for most cases of dementia. The currently approved therapy includes cholinesterase inhibitors, NMDA-receptor antagonists and monoclonal antibodies. However, these medications were gradually discovered to be ineffective in removing the root of AD pathogenesis, having only symptomatic effects. Thus, the priority remains prevention and clarifying AD etiology. A better understanding of the neuroprotective mechanisms undertaken by specific genes is crucial to guide the design of novel therapeutic agents via selective ligands and precision medicine. In this review, we present a perspective of the physiological phase of the AD spectrum, of risk factors in AD with a focus on therapeutic approaches in three categories: neurotransmitters/ion modulations, peptide deposit control and aspecific treatments, followed by a discussion of treatment limitations. An overview of innovative strategies and non-pharmaceutical ancillary support is given. Full article

Sourdough fermentation has emerged as a promising biotechnological approach to reducing gluten content and modifying gluten proteins in wheat-based products. This review assesses the current scientific literature on the enzymatic degradation and hydrolysis of gluten during lactic acid bacteria (LAB) sourdough fermentation. It explores implications for individuals with gluten-related disorders, including celiac disease, non-celiac gluten sensitivity and intolerance, as well as irritable bowel syndrome (IBS). In addition, LAB sourdough effect on fermentable oligo-, di-, monosaccharides and polyols (FODMAPs), amylase-trypsin inhibitors (ATIs), and phytate are revised. Selected homo- and heterofermentative LAB are capable of degrading gluten proteins, especially the polypeptides derived from the action of native cereal proteases. Mixed cultures of LAB degrade gluten peptides more effectively than monocultures. However, LAB sourdough is not sufficient to remove the toxic peptides to the minimal level (<20 ppm). This goal is achieved only if sourdough is combined with fungal proteases during sourdough fermentation. LAB sourdough directly contributes to lower FODMAPs but not ATIs and phytate. Phytate is reduced by the endogenous cereal phytases activated at acidic pHs (pH < 5.0), conditions generated during sourdough fermentation. ATIs are also lowered by endogenous cereal proteases instead of LAB proteases/peptidases. Despite LAB sourdough not fully degrading the gluten or directly reducing the ATIs and phytate, it participates through peptidases activity and acidic pH that trigger the action of endogenous cereal proteases and phytases. Full article

The substrate-induced respiration-inhibition (SIRIN) method has been used to estimate fungi-derived N₂O emissions, but its contribution to soil N₂O emissions remains unclear. There is a need to quantify the fungal fraction of N₂O production more precisely. Here, using isotopocule analysis, we assessed the relative contribution of fungi to soil N₂O production potential under denitrifying conditions, where key limiting factors of denitrification (soil moisture, soil NO₃⁻, and electron donor) were removed. The result showed that the ratio of fungi-derived N₂O emissions (R_F) was 0.83~4.28% in paddy soils, 13.80~23.21% in vineyard soils, and 15.34~65.94% in vegetable field soils, respectively. This indicated that the bacteria were the dominator of soil N₂O production potential in most cases, but fungal pathways could be significant in vegetable field soils. The experiment with bactericide addition showed that inhibitors could affect non-target microorganisms in the SIRIN method. Our further analyses suggest that it is worth to explore the effect of soil organic carbon and microbial synergies on fungi-derived N₂O emissions. Full article

Chronic kidney disease (CKD) is associated with the systemic accumulation of uremic toxins (UTs) due to impaired renal elimination. Among these, indoxyl sulfate (IS) and p-cresyl sulfate (PCS) are particularly challenging because of their high protein binding and limited removal by dialysis. In addition to renal excretion, the transport of IS and PCS, and their microbiota-derived precursors, indole and p-cresol, across key physiological barriers—the intestinal barrier, blood–brain barrier, and renal proximal tubule—critically influences their distribution and elimination. This review provides an overview of transporter-mediated mechanisms involved in the disposition of IS, PCS, and their microbial precursors, indole and p-cresol. It also examines how these UTs may interact with commonly prescribed drugs in CKD, particularly those that share transporter pathways as substrates or inhibitors. These drug–toxin interactions may influence the pharmacokinetics and toxicity of IS and PCS, but remain poorly characterized and largely overlooked in clinical settings. A better understanding of these processes may guide future efforts to optimize pharmacotherapy and support more informed management of CKD patients, particularly in the context of polypharmacy. Full article

Calcium (Ca²⁺) signaling is a fundamental regulatory mechanism controlling essential processes in the endothelium, vascular smooth muscle cells (VSMCs), and the extracellular matrix (ECM), including maintaining the endothelial barrier, modulation of vascular tone, and vascular remodeling. Cytosolic free Ca²⁺ concentration is tightly regulated by a balance between Ca²⁺ mobilization mechanisms, including Ca²⁺ release from the intracellular stores in the sarcoplasmic/endoplasmic reticulum and Ca²⁺ entry via voltage-dependent, transient-receptor potential, and store-operated Ca²⁺ channels, and Ca²⁺ elimination pathways including Ca²⁺ extrusion by the plasma membrane Ca²⁺-ATPase and Na⁺/Ca²⁺ exchanger and Ca²⁺ re-uptake by the sarco(endo)plasmic reticulum Ca²⁺-ATPase and the mitochondria. Some cell membranes/organelles are multifunctional and have both Ca²⁺ mobilization and Ca²⁺ removal pathways. Also, the individual Ca²⁺ handling pathways could be integrated to function in a regenerative, capacitative, cooperative, bidirectional, or reciprocal feed-forward or feed-back manner. Disruption of these pathways causes dysregulation of the Ca²⁺ signaling dynamics and leads to pathological cardiovascular conditions such as hypertension, coronary artery disease, atherosclerosis, and vascular calcification. In the endothelium, dysregulated Ca²⁺ signaling impairs nitric oxide production, reduces vasodilatory capacity, and increases vascular permeability. In VSMCs, Ca²⁺-dependent phosphorylation of the myosin light chain and Ca²⁺ sensitization by protein kinase-C (PKC) and Rho-kinase (ROCK) increase vascular tone and could lead to increased blood pressure and hypertension. Ca²⁺ activation of matrix metalloproteinases causes collagen/elastin imbalance and promotes vascular remodeling. Ca²⁺-dependent immune cell activation, leukocyte infiltration, and cholesterol accumulation by macrophages promote foam cell formation and atherosclerotic plaque progression. Chronic increases in VSMCs Ca²⁺ promote phenotypic switching to mesenchymal cells and osteogenic transformation and thereby accelerate vascular calcification and plaque instability. Emerging therapeutic strategies targeting these Ca²⁺-dependent mechanisms, including Ca²⁺ channel blockers and PKC and ROCK inhibitors, hold promise for restoring Ca²⁺ homeostasis and mitigating vascular disease progression. Full article

Background/Objectives: Treatment options for androgenic alopecia are still very limited and lack long-term efficacy. Dutasteride (DUT) has gained interest as a potent inhibitor of 5α-reductase, allowing for spaced applications, but DUT oral intake can cause serious adverse effects. Herein, we developed, characterized, and assessed the potential of DUT-loaded ethosomes with increasing ethanolic concentrations for hair follicle (HF) targeting to treat androgenic alopecia, hypothesizing that ethanol’s interaction with HFs’ sebum might increase DUT targeting to the HFs. Methods: Ethosomes were obtained using the water-dropping method. After a hydrodynamic size screening, a 30% ethanol concentration was fixed. Ethosomes with 30% ethanol were also prepared and had their ethanolic content removed by rotary evaporation for the evaluation of ethanol in targeting DUT to the HFs. The targeting factor (Tf) was calculated as the ratio between the DUT amount in HFs and the total DUT amount recovered from all skin layers after in vitro porcine skin penetration tests for 12 and 24 h. Results: The ethanolic concentration affected the vesicles’ size and the targeting potential. While the dried ethosomes could not increase DUT accumulation in the HFs at both time points (Tf: 0.27 in 12 h and Tf: 0.28 in 24 h), the presence of 30% ethanol in the vesicles increased the Tf from 0.28 (12 h) to 0.34 (24 h), significantly superior (p < 0.05) than the dried ethosome and control (Tf: 0.24) in 24 h. Conclusion: Ethosomes with a 30% ethanolic concentration were slightly more efficient in targeting HFs for dutasteride delivery. Full article

Asthma is a chronic inflammatory airway disease that can be aggravated by metabolic comorbidities such as type 2 diabetes mellitus (DM2) and obesity. Elevated levels of methylglyoxal (MGO), a reactive glycolysis byproduct, have been associated with exacerbation of allergic airway disease. SGLT2 inhibitors have been successfully employed in DM2 treatment. Here, we hypothesized that elimination of MGO might be a potential anti-inflammatory mechanism of SGLT2 inhibitors. This study aimed to evaluate the effects of empagliflozin on ovalbumin (OVA)-induced airway inflammation in mice chronically exposed to MGO. Male C57BL/6 mice sensitized with OVA were exposed to 0.5% MGO for 12 weeks and treated with empagliflozin (10 mg/kg, gavage, two weeks). MGO exposure significantly enhanced airway eosinophil infiltration, mucus production and collagen deposition, as well as levels of IL-4, IL-5, eotaxin and TNF-α. Empagliflozin treatment significantly reduced OVA-induced airway disease, which was accompanied by reductions in IgE, IL-4, IL-5, eotaxin, and TNF-α levels. Empagliflozin significantly reduced the MGO levels in serum, and immunohistochemical staining, and protein expression of MGO-hydroimidazolone (MG-H1), while increasing IL-10 levels and glyoxylase-1 (GLO 1) activity in lungs. In conclusion, empagliflozin efficiently removes MGO from circulation, while increasing the MGO detoxification by GLO 1, thereby mitigating the OVA-induced inflammation in MGO-exposed mice. Full article

Cellular senescence is a fundamental mechanism in aging, marked by irreversible growth arrest and diverse functional changes, including, but not limited to, the development of a senescence-associated secretory phenotype (SASP). While transient senescence contributes to beneficial processes such as tissue repair and tumor suppression, the persistent accumulation of senescent cells is implicated in tissue dysfunction, chronic inflammation, and age-related diseases. Notably, the SASP can exert both pro-inflammatory and immunosuppressive effects, depending on cell type, tissue context, and temporal dynamics, particularly in early stages where it may be profibrotic and immunomodulatory. Recent advances in senotherapeutics have led to two principal strategies for targeting senescent cells: senolytics, which selectively induce their apoptosis, and senomorphics, which modulate deleterious aspects of the senescence phenotype, including the SASP, without removing the cells. This review critically examines the molecular mechanisms, therapeutic agents, and clinical potential of both approaches in the context of anti-aging interventions. We discuss major classes of senolytics, such as tyrosine kinase inhibitors, BCL-2 family inhibitors, and natural polyphenols, alongside senomorphics including mTOR and JAK inhibitors, rapalogs, and epigenetic modulators. Additionally, we explore the biological heterogeneity of senescent cells, challenges in developing specific biomarkers, and the dualistic role of senescence in physiological versus pathological states. The review also highlights emerging tools, such as targeted delivery systems, multi-omics integration, and AI-assisted drug discovery, which are advancing precision geroscience and shaping future anti-aging strategies. Full article

The current treatment for refractory BRAF-V600E mutant metastatic colorectal cancer (mCRC) involves combined inhibition of BRAF and the epidermal growth factor receptor (EGFR). However, tumour responses are often short-lived due to a rebound in mitogen-activated protein kinase (MAPK) activity. In this study, we combined short-term cell viability assays with long-term regrowth assays following drug removal over a period of three weeks. This allowed assessment of regrowth after therapy discontinuation. We tested the effect of combined BRAF inhibition (encorafenib) and EGFR inhibition (afatinib) on BRAF-V600E mutant CRC patient-derived organoids (PDOs). Combined EGFR/BRAF inhibition initially caused a major reduction in PDO growth capacity in BRAF-V600E mutant PDOs. This was followed by rapid regrowth after drug removal, mirroring clinical outcomes. EGFR inhibition in BRAF-V600E mutant PDOs led to activation of the insulin receptor (IR) and insulin-like growth factor-1 receptor (IGF1R). The IGF1R/IR inhibitor linsitinib prevented the rebound in MAPK activity following removal of afatinib and encorafenib, prevented regrowth of CRC PDOs, and improved the anti-tumour response in an in vivo model. PDO regrowth assays allow the identification of pathways driving tumour recurrence. IR/IGF1R-inhibition prevents regrowth following golden standard MAPK pathway-targeted therapy and provides a strategy to improve the treatment of BRAF-V600E mutant CRC Full article

Produced water is the waste aqueous phase from petroleum extraction. As it contains salts, a high organic load, and toxic organic compounds, it should be treated before disposal or reuse. In this research, the combination of membrane processes (microfiltration or membrane distillation) with TiO₂-based heterogeneous photocatalysis was assessed to treat synthetic produced water. Pre-treatment with both microfiltration and membrane distillation removed the majority (90–98%) of large organic compounds (humic acids) from produced water. Moreover, membrane distillation also eliminated salt (sodium chloride). However, membrane processes only removed 10–50% of phenol, used here as proxy for low-molecular-weight toxic organic compounds. For this reason, membrane permeates, from microfiltration and membrane distillation, underwent a further photocatalytic treatment aimed at phenol degradation. The application of TiO₂ photocatalysis to membrane distillation permeates was successful (100% phenol removal in 5 min), while the high chloride concentration of microfiltration permeates acted as inhibitor of the photocatalytic process. Overall, good-quality water may be obtained from the combination of membrane distillation and heterogeneous photocatalysis, which performed much better than the two techniques used separately. Indeed, while membrane distillation was not able to remove phenol, produced water was too complex a matrix to be effectively treated with TiO₂/UV photocatalysis alone. Full article

Background/Objectives: Biocorrosion, driven by microbial colonization and biofilm formation, poses a significant threat to the integrity of metal artifacts, particularly those composed of copper and its alloys. Pseudomonas aeruginosa, a bacterial species that reduces nitrates, plays a key role in this process. This study explores the potential of two metabolite-rich plant extracts, Aloe vera and Opuntia ficus-indica, as sustainable biobased inhibitors of microbial-induced corrosion (MICOR). Methods: The antibacterial and antibiofilm activities of the extracts were evaluated using minimal inhibitory concentration (MIC) assays, time-kill kinetics, and biofilm prevention and removal tests on copper, bronze, and brass samples. Spectrophotometric and microbiological methods were used to quantify bacterial growth and biofilm density. Results: Both extracts exhibited significant antibacterial activity, with MIC values of 8.3% (v/v). A. vera demonstrated superior bactericidal effects, achieving reductions of ≥3 log₁₀ in bacterial counts at lower concentrations. In antibiofilm assays, both extracts effectively prevented biofilm formation and reduced established biofilms, with A. vera exhibiting greater efficacy against them. The active metabolites—anthraquinones, phenolics, flavonoids, and tannins—likely contribute to these effects. Conclusions: These findings highlight the dual role of A. vera and O. ficus-indica extracts as both corrosion and biocorrosion inhibitors. The secondary metabolite profiles of these plants support their application as eco-friendly alternatives in the conservation of metal cultural heritage objects. Full article